John Hancock must have been an egomaniac. Large signatures are common among narcissists, finds new research from the University of North Carolina's Kenan-Flagler Business School and the University of Maryland. The study examined the signatures of more than 600 CEOs and found that the most outsized signers were among the highest paid, but were also more likely to run their companies into the ground. Those factors indicate an inflated sense of self, a disregard for people's input, and other narcissistic tendencies, explains study author Nicholas Seybert, Ph.D., an assistant professor at the University of Maryland. (Okay, it isn't a man's world anymore. Narcissism notwithstanding, are there any advantages to being guy?)

Past research shows large signatures reveal high self-esteem and social dominance among the general public. Why? People see a signature as a stand-in for themselves, and a bigger, more prominent moniker reveals a person's larger-than-average self-regard, the research explains. If you have a big autograph, you're not necessarily a narcissist--though you probably are an alpha male, Seybert says. But when applied to CEOs--a group already likely to favor people with inflated egos--big signatures are also likely to reveal narcissistic traits. (Avoid the 5 ways to ruin a first impression, and ace that crucial first date.)

Here are more strange clues into your personality.

If you love boiled eggs, you're more likely to be messy.Boiled egg lovers are more disorganized and more likely to get divorced, shows a study of 1,100 people funded by the British Egg Industry Council and published by Mindlab International. Fried egg fans have the highest sex drive, the study finds. Poached-egg eaters are outgoing and happy, scrambled aficionados are guarded, and omelet lovers are self-disciplined, the study says.

If you drive a red car, you're more reckless.People who drive red cars are more aggressive and reckless, shows a study from CW Marketing Research. The Oregon-based firm also found people with green cars have the most positive outlook on life, dark blue or silver-car owners are upbeat, and black car owners lack self-confidence. Why? A growing body of research shows certain visual cues--such as colors--are tied to emotional and behavioral cues in your brain. These cues can influence the colors you find appealing depending on your personality type, according to a University of Cambridge study. (And while you're in the car, make sure to eat smart. Grab a copy of Eat This, Not That! 2013 for your next road trip.)

If you have too many Post-it Notes, you're probably overwhelmed. An empty or unpersonalized desk indicates a lack of dedication or job dissatisfaction, according to a University of Texas study. Excessive Post-it Notes mean you're overwhelmed, while a plant proves you have no plans to leave your gig, the UT study shows. The researchers say people see their personal space as extensions of themselves, and so how they arrange or design those spaces provide clues to their personalities. People who have candy bowls or lots of office supplies are more likely to be outgoing and social, and motivational items often reveal a worker who pushes himself, the study adds.

If you love Metallica, you're more likely to be lazy.Classical, jazz, and heavy metal music lovers are all generally creative and at ease, but metal-heads are more likely to also be lazy and introverted, finds a study of 36,000 people from Scottish researchers. Blues fans tend to have high self-esteem, rap fans are pretty outgoing, and country lovers are generally hardworking, the study shows. Indie rock snobs tend to be harsh and lack self-esteem, the study found. (Discover the 6 crazy ways music improves your life.)